error[E0502]: cannot borrow `x` as immutable because it is also borrowed as mutable --> $DIR/method-self-arg-2.rs:15:14 | LL | let y = &mut x; | ------ mutable borrow occurs here LL | Foo::bar(&x); | ^^ immutable borrow occurs here LL | y.use_mut(); | ----------- mutable borrow later used here error[E0499]: cannot borrow `x` as mutable more than once at a time --> $DIR/method-self-arg-2.rs:20:14 | LL | let y = &mut x; | ------ first mutable borrow occurs here LL | Foo::baz(&mut x); | ^^^^^^ second mutable borrow occurs here LL | y.use_mut(); | ----------- first borrow later used here error: aborting due to 2 previous errors Some errors have detailed explanations: E0499, E0502. For more information about an error, try `rustc --explain E0499`.